fix: log only if transaction exists (#2862)

Author: bruno-garcia

src/Sentry/Internal/Hub.cs

@@ -437,12 +437,12 @@ SentryId IHubEx.CaptureEventInternal(SentryEvent evt, Hint? hint, Scope? scope)
             actualScope.LastEventId = id;
             actualScope.SessionUpdate = null;
 
-            if (evt.HasTerminalException())
+            if (evt.HasTerminalException() && actualScope.Transaction is { } transaction)
             {
                 // Event contains a terminal exception -> finish any current transaction as aborted
                 // Do this *after* the event was captured, so that the event is still linked to the transaction.
                 _options.LogDebug("Ending transaction as Aborted, due to unhandled exception.");
-                actualScope.Transaction?.Finish(SpanStatus.Aborted);
+                transaction.Finish(SpanStatus.Aborted);
             }
 
             return id;